Mono Red Rally wants to go wide and then alpha-strike with Rally at the Hornburg or Goblin Bushwhacker, so Weather the Storm's storm-copied 3-life gain per spell is excellent insurance against a single lethal turn, especially once they've already cast a few cheap spells that turn. Campfire and Lembas gain life too slowly and inefficiently compared to Weather the Storm's burst potential against a combo-aggro deck racing to one big turn. Keep removal like Cast Down and Unmake in since killing Burning-Tree Emissary, Clockwork Percussionist, or Kor Skyfisher-style enablers before the big turn is still the best way to disrupt their mana-neutral sequencing.